Production of unsaturated organic compounds



Patented June 5, 1928.

UNITED STATES PATENT OFFICE.

won FBEUND, or BERLIN, GERMANY,

acrmnzwomr. a. scnnnmo),

ASSIGHOR TO CHEHISCHE FABBIK AU! 01' BERLIN, GERMANY.

?BODUCTION OF UNSATUBATED ORGANIC COMPOUNDS.

My invention relates to the catalytic production of unsaturated organic compounds from their corresponding hydroxyl compounds in a more efficient manner than was 6 hitherto possible.

It is known that such production has been hitherto performed by means of aluminium-, thoriumor cerium oxides.

I have found that better results than are 10 obtained by these substances can be obtained by other catalyzers which are characterized by chemical indiflierence as to the hydroxyl compounds in question and by a high degree of porosity, such as or siliceous clays, and other aluminum magnesium hydrosilicates, as for instance the products signified by the trade names, Frankonites, Tonsil and the like. The dehydrating action of these catalyzers on hydroxyl compounds of the type R HOH I R! R!!! where the R, R, R and R signify any monovalent groups, can be explained as surface catalysis. The superiority over the catalyzers used up to the present may be shown as follows: According to Ipatiew (Berichte 3o der deutschen chemischen Gesellschaft, volume 43, page 3383) the dehydration of c 'clohexanol in presence of aluminium oxi e requires a temperature of 400 C. and a hydrogen ressure of 40 atmospheres. When any of t e catalyzers above described is used,

instead of the aluminium oxide, dehydration begins below the boiling point of cyclohexanol, and this substance is decomposed into water and cyclohexen.

The process may be illustrated by the following examples:

1. 100 parts of cyclohexanol and 2 parts of Frankonite are distilled from a retort, the temperature beingoso re ulated, that only 45 the constituents iling elow C. are

fullers earth ble ching condensed. The distillate will then consist of a mixture of water and cyclohexene, which can easily be separated, yielding pure tetrahydrobenzene.

2. parts of glycerine, desiccated at degrees centigrade are distilled with 5 parts of infusorial silica. Pure acrolein will be obtained. I

3. 100 parts of borneol a boiled with 5 parts of-a bleaching clay consisting of aluminum magnesium hydrosilicate. A mixture of camphene and water will be condensed, from which camphene ma be obtained by crystallization or rectification.

In an analogous way other unsaturated compoundsean be obtained and other catalyzers of the described manner may be used.

I wish it to be understood that my invention is not confined to these examples and to the proportions described, for obvious modifications will occur to a person skilled in the art.

In the following claims, the ex ression aliphatic system is intended to inc ude aliphatic chain systems as well as alicyclic ring systems. Y

I claim as my invention:

1. The method of producing unsaturated organic compounds, which comprises heating an organic compound which carries hydrogen and hydrox l on two adjacent carbon atoms in an a iphatic system, with a bleaching earth as a catal zer, and then so arating the unsaturat compound us formed.

2. The method of producing unsaturated organic compounds which comprises dehydrating or anic com ounds that carry hydrogen an hydroxy on two adjacent carbon atoms in an a iphatic system, by the iatalytic action of a bleaching earth and eat.

In testimony whereof I have hereunto set my signature.

Da. ERICH FBEUND.

and in Germany September 83, 1981. 

